<template>
	<div class="mbx-box">
		<el-breadcrumb class="app-breadcrumb" separator="/">
			<transition-group name="breadcrumb">
				<el-breadcrumb-item v-for="(item,index) in levelList" :key="item.path">
					<span v-if="(item.redirect==='noRedirect'||index==levelList.length-1)" class="no-redirect">
						{{ item.meta.title }}
					</span>
					<a v-else @click.prevent="handleLink(item)" style="color: #fff;">{{ item.meta.title }}</a>
				</el-breadcrumb-item>
			</transition-group>
		</el-breadcrumb>
	</div>
</template>

<script>
	import pathToRegexp from 'path-to-regexp'

	export default {
		data() {
			return {
				levelList: null
			}
		},
		watch: {
			$route(route) {
				// if you go to the redirect page, do not update the breadcrumbs
				if (route.path.startsWith('/redirect/')) {
					return
				}
				this.getBreadcrumb()
			}
		},
		created() {
			this.getBreadcrumb()
		},
		methods: {
			getBreadcrumb() {
				// only show routes with meta.title
				let matched = this.$route.matched.filter(item => item.meta && item.meta.title)
				const first = matched[0]

				if (!this.isDashboard(first)) {
					if (this.$route.fullPath !== '/dashboard') {
						matched = [{
							path: '/dashboard',
							meta: {
								title: '首页'
							}
						}].concat(matched)
					}
				}

				this.levelList = matched.filter(item => item.meta && item.meta.title && item.meta.breadcrumb !== false)
			},
			isDashboard(route) {
				const name = route && route.name
				if (!name) {
					return false
				}
				return name.trim().toLocaleLowerCase() === 'Dashboard'.toLocaleLowerCase()
			},
			pathCompile(path) {
				// To solve this problem https://github.com/PanJiaChen/vue-element-admin/issues/561
				const {
					params
				} = this.$route
				var toPath = pathToRegexp.compile(path)
				return toPath(params)
			},
			handleLink(item) {
				const {
					redirect,
					path
				} = item
				if (redirect) {
					this.$router.push(redirect)
					return
				}
				this.$router.push(this.pathCompile(path))
			}
		}
	}
</script>

<style scoped>
	.mbx-box {
		width: calc(100% - 30px);
		height: 20px;
		background-image: linear-gradient(to right, rgba(59, 217, 231, 0.4), rgba(59, 217, 231, 0.1), transparent);
		display: inline-block;
	}

	.mbx-box::before {
		content: '';
		width: 5px;
		height: 20px;
		position: absolute;
		left: -20px;
		top: 0;
		background-color: rgba(59, 217, 231, .7);
	}

	.mbx-box::after {
		content: '';
		width: 5px;
		height: 20px;
		position: absolute;
		left: -10px;
		top: 0;
		background-color: rgba(59, 217, 231, .7);
	}
</style>

<style lang="scss" scoped>
	.app-breadcrumb.el-breadcrumb {
		font-size: 12px;
		width: calc(100% - 20px);
		height: 20px;
		line-height: 20px;
		padding: 0 15px;
		transform: skew(35deg);

		.no-redirect {
			cursor: text;
			color: #fff;
		}
	}
</style>
